Astaxanthin Production by P. rhodozyma

The strain JMU-MVP14 of P. rhodozyma (Li et al., 2022 (link); Xiao et al., 2015 (link); Yang et al., 2023 (link)) was obtained from the strain bank of the Fujian Key Laboratory of Food Microbiology and Enzyme Engineering. Astaxanthin standard products were purchased from Yuanye Biotechnology Co., Ltd (SHH, CHN). 3,5-Dinitrosalicylic acid reagent (DNS) was purchased from Fei Jing Biotechnology Co., Ltd (FJ, CHN). Methanol (chromatographic grade) was purchased from Sigma–Aldrich (CA, USA). Moreover, dimethyl sulphoxide, anhydrous ethanol, glucose, magnesium sulphate heptahydrate, calcium chloride dihydrate, sodium chloride, potassium dihydrogen phosphate, ammonium sulphate, and so on were all analytically pure and purchased from Sinopharm Chemical Reagent Co (SHH, CHN). Yeast extract powder and tryptone were purchased from Huankai Microbial Technology Co., Ltd (GD, CHN). TiO₂ was analytical grade, purchased from Xilong Science Co., Ltd (GD, CHN).